US Patent 7142931 Control system with controlled dead zone

A method of operating a control device having a setpoint value, an error signal, and a control output is disclosed. The error signal is representative of a difference between a controlled variable and the setpoint value, the control output operable to affect the controlled variable. The method includes generating the control output based at least in part on the error signal and holding the control output at a held value independent of the error signal when the error signal is within a dead zone. The method also includes causing an integrating portion within the control device to track the error signal and the held value when the error signal is within the dead zone.